Razor blades are typically formed of a suitable metallic sheet material such as stainless steel, which is slit to a desired width and heat-treated to harden the metal. The hardening operation utilizes a high temperature furnace, where the metal may be exposed to temperatures greater than 1145° C. for up to 18 seconds, followed by quenching.
After hardening, a cutting edge is formed on the blade. The cutting edge typically has a wedge-shaped configuration with an ultimate tip having a radius less than about 1000 angstroms, e.g., about 200-300 angstroms.
The razor blades are generally mounted on bent metal supports and attached to a shaving razor (e.g., a cartridge for a shaving razor). FIG. 1, for example, illustrates a prior art razor blade assembly that includes a planar blade 10 attached (e.g., welded) to a bent metal support 11. Blade 10 includes a tapered region 14 that terminates in a cutting edge 15 16. This type of assembly is secured to shaving razors (e.g., to cartridges for shaving razors) to enable users to cut hair (e.g., facial hair) with cutting edge 16. Bent metal support 11 provides the relatively delicate blade 10 with sufficient support to withstand forces applied to blade 10 during the shaving process. Examples of razor cartridges having supported blades are shown in U.S. Pat. No. 4,378,634 and in U.S. patent application Ser. No. 10/798,525, filed Mar. 11, 2004, which are incorporated by reference herein.